Effects of dexamethasone on bovine circulating T lymphocyte populations

Abstract: In cattle, y#{246}T cells represent a higher proportion of circulating T cells than in humans. Bovine?#{246}T cells can be recognized by expression of ‘y6 T cell receptor (‘y#{246}TCR) determinants or by a 2i5/230-kDa surface antigen (WC1). WC1 is ex-pressed on 90 % or more of circulating bovine y#{246}T cells. The effects ofdexamethasone on this and other subsets (CD3, CD2, CD4, CD8) of peripheral blood T lymphocytes were determined by flow cytometric analysis. Twelve 15-month old bulls were injected with dexamethasone (0.04 mg/kg/day) for 3 consecu-tive days and four bulls were untreated controls. Blood samples were collected daily for 3 days before dexamethasone injections and for an additional 7 days starting on the third injection day. Data wer